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Pelvic Frx: Selection of Pins and Frame Type

- Pin Diameter and Length:
    - pins should be at least 5 mm in diameter (such as the Orthofix 6/5 mm self tapping screws);
    - resistance to cephalad displacemnt could be approximately doubled by using 5 mm vs. 4 mm half pins for iliac wing fixation, & is further enhanced by adding a second pin group in each ilium between anteroinferior and superior iliac spines;
           - smaller pelves, however, require 4-mm pins to avoid comminution of iliac wing & loss of purchase;
           - osteoporotic pelvis in the elderly patient may not hold pins well.
    - pin length:
           - use pins with adequate length, to allow for postoperative swelling and the need for anteriorization of the frame;

- Frame Type:
    - it is helpful to construct the frame prior to surgery;
    - consider using a double frame construct;
           - this will allow for postoperative manipulation of one frame without losing the reduction (since the second frame is in place);
           - avoid placing cross bars between the two frames since this will complicate postoperative frame manipulation;
    - care must be taken to avoid placing clamps too close to abdomen, particularly in acute situation in which abdominal distension will cause frame impingement;
           - always build into the frame the option of increasing the frame's girth in order to allow for postoperative frame manipulation should swelling occur

External fixation of unstable Malgaigne fractures: the comparative mechanical performance of a new configuration.

Anatomic and radiographic considerations in the placement of anterior pelvic external fixator pins.

Biomechanical testing of new and old fixation devices for vertical shear  fractures of the pelvis.